Recent advances in enyne metathesis in non-usual media

This review presents seminal advancements in enyne metathesis in nonusual media, including green solvents, supercritical fluid, and microwave technology. Enyne metathesis has been recognized as a powerful and innovative transformation in modern molecular chemistry, enabling the efficient construction of complex cyclic and acyclic diene frameworks. One can differentiate the enyne cross-metathesis, where an alkyne may react with an alkene, from the ring-closing enyne metathesis, where the alkyne and alkene are part of the same molecule. Both enyne transformations will be discussed in various solvents such as water, ionic liquids, ethyl lactate, and dimethyl carbonate. The use of various ruthenium-based complexes will be compared in each case. We will finally present tandem processes implying enyne cross- or ring-closing metathesis and cyclization or reduction.